Berkowitz listed on a courtroom screen 11 reasons Skilling had cited in his testimony for leaving Enron, chief among them to spend time with his family.

Berkowitz then pulled a surprise: Shortly after he left Enron, Skilling had a conversation with an old friend in which Skilling said he was considering taking the job as chief executive at Lucent Technologies, the prosecutor said.

The government alleges that Skilling -- charged with 28 counts of fraud, conspiracy and insider trading for his role in the collapse of Enron in December 2001 -- left the company because he knew it was about to collapse, not because he wanted to take some time off from the high-pressure world of being a corporate executive, as Skilling has testified. The Lucent revelation is meant to underscore that assertion.

Skilling denied that he told friend Dick Foster that he was interested in taking the Lucent job, only that it had been brought up.

Berkowitz asserted that Foster became angry with Skilling and said, "Jeff, I thought this (leaving Enron) was about your family." Foster then called Enron chief executive Kenneth Lay and an Enron board member to tell them the Lucent news and they were "incredulous," Berkowitz said.

Skilling said he did not know about the calls, but Foster's blowup over drinks "is part of the reason why Mr. Foster and I are no longer close."

Just before, Berkowitz had walked Skilling through several of the problems -- Skilling called them "issues" -- Enron was facing when he left the company: Trouble with California energy regulators, an inability to sell Enron's international assets without losing money on them, problems with the company's power plant in India, which was not getting paid for the power it was producing, and a number of personal reasons, all of which Skilling agreed with.

This line of questioning was meant to counter Skilling's asserting that Enron was in sound condition when he left.

Earlier, Skilling and Berkowitz engaged in a testy back-and-forth session, much of it in the form of eye-glazing testimony about risk analysis.

Berkowitz is attempting to show that Skilling dangerously increased the amount of risk Enron was undertaking in 2000 and 2001, as the California energy crisis was under way, and attempted to use Skilling's own words against him.

Skilling, who is undergoing his third day of cross-examination, said that every business takes risks, that Enron's were well within its acceptable parameters and that investors understood this.

Berkowitz disagreed, saying Skilling had attempted to flummox investors with highly technical language and doublespeak during calls with financial analysts.

Much of the testimony focused on Enron's VAR, its "value at risk" methodology. Each day, Enron fed several factors -- such as energy prices and the value of its hedges -- into a super-computer called the "VAR engine." The computer would spit out a number that Enron used to set the ceiling of its acceptable risk in how far it was willing to extend itself when buying and selling natural gas and electricity.

Berkowitz argued that Skilling tried to snow investors who were worried about how skyrocketing energy prices in California would affect Enron.

The prosecutor played clips of Skilling in television interviews at the time, saying the company had "virtually no exposure to commodity prices," meaning prices for natural gas and electricity.

"Your gains and losses were the result of commodity price positions, right?" Berkowitz asked.

"Right," Skilling said.

"You were telling the market you had no exposure?" Berkowitz asked.

"No, we were telling them our VAR exposure and this was well within our VAR exposure," Skilling said.

For must of the morning, Skilling appeared frustrated that he could not make Berkowitz understand how Enron worked and that nothing illegal had happened. Other times, Skilling got peeved at Berkowitz, which he reciprocated.

After one television clip, Skilling said, "Can we discuss this? This is a classic example. ..." But before he could continue, Berkowitz cut him off.

The government charges that Skilling and Lay -- who faces six counts of fraud and will take the stand after Skilling -- dipped into company reserves to bolster earnings, pump up the stock price and hide losses from investors.

Berkowitz questioned Skilling about Enron's exposure to wild price swings in the electricity markets, especially during the California energy crisis of 2000.

Skilling testified that analysts and investors who had followed Enron understood that the company's revenues were dependent on natural gas prices -- an exposure that, he said, was well within acceptable limits.

Then Berkowitz played a video clip from a Bloomberg news service interview of Skilling at the time, in which Skilling said: "We have worked hard to basically eliminate all commodity exposure in the company. We are indifferent to those commodity prices."

Berkowitz attempted to use time-stamped Enron electronic calendar entries to prove that a 2001 meeting between Skilling and other top company officials was a hastily called summit where measures were discussed to conceal Enron losses associated with the California energy crisis of the time.

Skilling maintained the meeting was set well in advance and was meant to discuss the integration of the company's retail and wholesale energy trading units.

But Berkowitz showed that the meeting was entered into the executives' calendars the day of the meeting or the day before. Berkowitz is attempting to prove a pattern of deception by Skilling.

Skilling has maintained his innocence, saying the implosion of Enron -- once the nation's seventh-largest company -- was caused by a failure of investor confidence and a classic "run on the bank."

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